Bleaching fibers.



FIPEESOB ca enemas WLANKEZNT CHEWQAL rvomH- UNITED STATES PATENT OFFICE.

JAMES WAKEFIELD, or OOOKERMOUTH, ENGLAND.

BLEACHING FIBERS.

Specification of Letters Patent.

Patented Jan. 9, 1906.

Application filed September 15, 1904. Serial No. 224,547. (Specimens) To all whom it may concern:

7 Be it known that I, JAMES WAKEFIELD, a British subject, and a resident of Cockermouth, county of Cumberland, England, have invented certain new and useful Improvements in the Bleaching of Textile Fabrics and Fibers, of which the following is a specification.

This invention relates to an improved process for the bleaching of fabrics or fibers of vegetable origin, more particularly linen and hemp.

The process consists, essentially, in treating the material in a bath comprisinga mixed solution of bleaching-powder and permanganate of potash and then clearing or washing with an acidulated solution of bisulfite of soda.

I prepare a bath composed of a combination of the two bleaching agents, bleaching-powder (CahQGlO) and permanganate of potash (KMnO4) or permanganate of soda, (NaMnOiJ This is prepared to a suitable strength or density, according to the material to be treated. I also prepare in a second bath a solution of bisulfite of soda acidulated with sulfuric acid. Instead of supplying a second bath of bisulfite of soda an aqueoussolution of sulfurous acid or other suitable clearing agent may be employed. The proportions of the bleaching agents employed will vary with the quality of the material to be treated; but I find that the following proportions, as an example, give a good three-quarter bleach upon linen.

Example: For one hundred pounds of linen yarn in one hundred and thirty gallons of water:

Bath 1. Eight gallons of 10 Twaddell solution of bleaching-powder, two pounds of permanganate of potash.

Bath 2. Seven pounds of bisulfite of soda containing sixty per cent. S02, three-fourths pint of sulfuric acid.

Bath Three and one-half gallons of 10 Twaddell solution of bleaching-powder, six ounces of permanganate of potash.

Bath .4. Two and one-half pounds bisulfite of soda containing sixty per cent. S02, onehalf pint of sulfuric acid.

The material to be bleached after being well boiled is first treated in bath No. 1 for the necessary length of timesay for about two to three hoursand when removed therefrom is well washed in water. It is next treated in bath N 0. 2 until cleared-say for about one and I one-half hours-and then again well washed. The operation is then repeated in baths Nos. 3 and 4, which are weaker than the first two. This will give about a three-quarter bleach on linen goods. If full bleach is required, thematerial should receive a slight boil after N o. 4 bath and the treatment repeated in baths Nos. 3 and 4 at about half the strength. For hemp the baths may be made somewhat stronger and for cotton about half strength. The material is subsequently washed with water, dried, and finished in the usual way.

What I claim as my invention, and desire to protect by Letters Patent, is-

1. The process of bleaching textile yarn or fabrics of vegetable origin which consists in treating the material with a mixed solution of bleaching-powder and permanganate of potash and then with bisulfite of sodain solution, substantially as described.

2. The process of bleaching textile yarns 0r fabrics of vegetable origin which: consists in treating the material with a mixed solution of bleaching-powder and permanganate of potash and then with an acidulated solution of a J AS. WAKEFIELD.

Witnesses:

J. OWDEN OBRIEN, B. LATHAM WOODHEAD. 

